a. Field of the Invention
The present invention relates to socks, particularly to socks characterized in structure of a heel part thereof and a knitting method therefor.
b. Description of the Prior Art
While socks, such as sports socks, are used daily or when some sport is played, the heel part is liable to slip down when a wearing person moves violently or in a like case. The slipping down knit fabric accumulates at the foot part and deteriorates the wearing feeling, and with such socks as ankle socks, it sometimes deteriorates also the appearance.
Further, the knit fabric at a portion around the heel sometimes gives some tightened feeling to the wearing person and deteriorates the feeling of use of the socks, and this gives rise to pulling down of the knit fabric at the heel part during use and results in accumulation of the fabric at the sole part.
Therefore, ankle socks have been proposed wherein a projection like a dingdong in the form of a ball is provided at an upper edge of a heel part such that, when a person puts on the socks and then puts on shoes, the projections may engage with upper portions of the heel parts of the shoes to prevent the socks from slipping down into the shoes during walking. However, where this structure is employed, time and labor are required to attach the projections by sewing after the socks are knitted. Further, when slipping down of socks itself occurs during walking and the fabric at the heel part is pulled down and slips down, an upper edge of the heel part of the sock comes to be exposed just outside the shoe due to the projection, which deteriorates the wearing feeling very much, and it is difficult to prevent slipping down of the knit fabric during walking.
The knit fabric of a portion which surrounds the heel, that is, the heel part of socks, is knitted next to knitting of a leg part which is knitted circumferentially into a tubular form. However, upon knitting of the heel part, circumferential knitting of the leg portion is stopped, and knitting is performed by reciprocating rotations over one half circumference. Besides, at each of end portions of the reciprocating motions, the number of needles for knitting is decreased by one for each one reciprocating motion. As a result, a knit fabric of a trapezoidal shape is produced. After a predetermined number of reciprocating motions, now a stitch is increased for each one reciprocating motion conversely while loops at end portions which form inclined sides of the trapezoidal knit fabric knitted already as described above are knitted. Then, when the original knitting width is reached, the knitting of the heel part is stopped and circumferential knitting is started to start knitting of the foot part, thereby to make a swell of the heel part.
By the knitting described above, two symmetrical trapezoidal knit fabrics wherein the opposite side edges formed as inclined sides are connected to each other are produced, and this part serves as the heel part of the socks. Connected portions of the two trapezoidal knit fabrics appear linearly and are called gore line. When it is considered that even the swell of the heel part is not sufficient, also socks wherein a linear gore line is bifurcated at a lower end portion thereof such that it may have an inverted Y-shape and socks wherein a gore line has a shape of overlapping Y-shapes such that it looks like a bone of a fish have been proposed.
However, even if only an end of a gore line is bifurcated into a Y-shape to increase the heel part of the knit fabric, the knit fabric of the heel part is knitted from the beginning to the ending of reciprocating knitting over a half circumference described above, and cannot be formed as a knit fabric which embraces the heel portion of a foot over a wide range.